offset on 92-95 civics

I have been searching around for rims and keep seeing a pattern of offsets on rims for Civics.

+40 offset seems to be popular.

From what I know...offset is the difference from the center of the wheel and where the lug nuts actually attach. Positive offsets mean the face of the rim is towards the outside (for front wheel drive cars) Negative offsets are for a deeper dish wheel (like pick-ups)

So a +55 offset would be sucked in to the center of the car....?

Saw some 16" Fit wheels that looked cool but I think you'd need spacers to make them work....if I am right about the difference in the offsets. But what do spacers do to the rigidity and drive of the car?

+33 offset .....so they are pushed to the outside of the car in comparison to +55 offset which is sucked inside more....right? The +33 looks good....very much on te outside part of it all. I can see how +40 is ideal for getting to the outside lip but letting you tuck still.

If I'm right about the tire on the car...then I'm only going 68mph when my speedo says 70mph

I had my Girlfriend next to me on the phone and had her 70mph and my car said around 73mph. And those stupid speed postings on the road always tell me Im slower then what the speedo says.

If this is all true...then 205 45 16's will be great and I can go up to (I think) +38mm offset which will push me out another 17mm total and put my speedo in better shape. +40 offset will push it out 15mm more to the outside

Its close after measuring and I think I can get around 20mm towards the outside before rubbing the inner fender (super close)